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-rw-r--r--drivers/usb/gadget/Makefile2
-rw-r--r--drivers/usb/gadget/u_ether.c967
-rw-r--r--drivers/usb/gadget/u_ether.h83
3 files changed, 1051 insertions, 1 deletions
diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index 47ecb3a9b3a6..a53cdeb9481f 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -25,7 +25,7 @@ obj-$(CONFIG_USB_M66592) += m66592-udc.o
25C_UTILS = composite.o usbstring.o config.o epautoconf.o 25C_UTILS = composite.o usbstring.o config.o epautoconf.o
26 26
27g_zero-objs := zero.o f_sourcesink.o f_loopback.o $(C_UTILS) 27g_zero-objs := zero.o f_sourcesink.o f_loopback.o $(C_UTILS)
28g_ether-objs := ether.o usbstring.o config.o epautoconf.o 28g_ether-objs := ether.o u_ether.o $(C_UTILS)
29g_serial-objs := serial.o u_serial.o f_acm.o f_serial.o $(C_UTILS) 29g_serial-objs := serial.o u_serial.o f_acm.o f_serial.o $(C_UTILS)
30g_midi-objs := gmidi.o usbstring.o config.o epautoconf.o 30g_midi-objs := gmidi.o usbstring.o config.o epautoconf.o
31gadgetfs-objs := inode.o 31gadgetfs-objs := inode.o
diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c
new file mode 100644
index 000000000000..5458f43a8668
--- /dev/null
+++ b/drivers/usb/gadget/u_ether.c
@@ -0,0 +1,967 @@
1/*
2 * u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
3 *
4 * Copyright (C) 2003-2005,2008 David Brownell
5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
6 * Copyright (C) 2008 Nokia Corporation
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23/* #define VERBOSE_DEBUG */
24
25#include <linux/kernel.h>
26#include <linux/utsname.h>
27#include <linux/device.h>
28#include <linux/ctype.h>
29#include <linux/etherdevice.h>
30#include <linux/ethtool.h>
31
32#include "u_ether.h"
33
34
35/*
36 * This component encapsulates the Ethernet link glue needed to provide
37 * one (!) network link through the USB gadget stack, normally "usb0".
38 *
39 * The control and data models are handled by the function driver which
40 * connects to this code; such as CDC Ethernet, "CDC Subset", or RNDIS.
41 * That includes all descriptor and endpoint management.
42 *
43 * Link level addressing is handled by this component using module
44 * parameters; if no such parameters are provided, random link level
45 * addresses are used. Each end of the link uses one address. The
46 * host end address is exported in various ways, and is often recorded
47 * in configuration databases.
48 *
49 * The driver which assembles each configuration using such a link is
50 * responsible for ensuring that each configuration includes at most one
51 * instance of is network link. (The network layer provides ways for
52 * this single "physical" link to be used by multiple virtual links.)
53 */
54
55#define DRIVER_VERSION "29-May-2008"
56
57struct eth_dev {
58 /* lock is held while accessing port_usb
59 * or updating its backlink port_usb->ioport
60 */
61 spinlock_t lock;
62 struct gether *port_usb;
63
64 struct net_device *net;
65 struct usb_gadget *gadget;
66
67 spinlock_t req_lock; /* guard {rx,tx}_reqs */
68 struct list_head tx_reqs, rx_reqs;
69 atomic_t tx_qlen;
70
71 unsigned header_len;
72 struct sk_buff *(*wrap)(struct sk_buff *skb);
73 int (*unwrap)(struct sk_buff *skb);
74
75 struct work_struct work;
76
77 unsigned long todo;
78#define WORK_RX_MEMORY 0
79
80 bool zlp;
81 u8 host_mac[ETH_ALEN];
82};
83
84/*-------------------------------------------------------------------------*/
85
86#define RX_EXTRA 20 /* bytes guarding against rx overflows */
87
88#define DEFAULT_QLEN 2 /* double buffering by default */
89
90
91#ifdef CONFIG_USB_GADGET_DUALSPEED
92
93static unsigned qmult = 5;
94module_param(qmult, uint, S_IRUGO|S_IWUSR);
95MODULE_PARM_DESC(qmult, "queue length multiplier at high speed");
96
97#else /* full speed (low speed doesn't do bulk) */
98#define qmult 1
99#endif
100
101/* for dual-speed hardware, use deeper queues at highspeed */
102static inline int qlen(struct usb_gadget *gadget)
103{
104 if (gadget_is_dualspeed(gadget) && gadget->speed == USB_SPEED_HIGH)
105 return qmult * DEFAULT_QLEN;
106 else
107 return DEFAULT_QLEN;
108}
109
110/*-------------------------------------------------------------------------*/
111
112/* REVISIT there must be a better way than having two sets
113 * of debug calls ...
114 */
115
116#undef DBG
117#undef VDBG
118#undef ERROR
119#undef WARN
120#undef INFO
121
122#define xprintk(d, level, fmt, args...) \
123 printk(level "%s: " fmt , (d)->net->name , ## args)
124
125#ifdef DEBUG
126#undef DEBUG
127#define DBG(dev, fmt, args...) \
128 xprintk(dev , KERN_DEBUG , fmt , ## args)
129#else
130#define DBG(dev, fmt, args...) \
131 do { } while (0)
132#endif /* DEBUG */
133
134#ifdef VERBOSE_DEBUG
135#define VDBG DBG
136#else
137#define VDBG(dev, fmt, args...) \
138 do { } while (0)
139#endif /* DEBUG */
140
141#define ERROR(dev, fmt, args...) \
142 xprintk(dev , KERN_ERR , fmt , ## args)
143#define WARN(dev, fmt, args...) \
144 xprintk(dev , KERN_WARNING , fmt , ## args)
145#define INFO(dev, fmt, args...) \
146 xprintk(dev , KERN_INFO , fmt , ## args)
147
148/*-------------------------------------------------------------------------*/
149
150/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
151
152static int eth_change_mtu(struct net_device *net, int new_mtu)
153{
154 struct eth_dev *dev = netdev_priv(net);
155 unsigned long flags;
156 int status = 0;
157
158 /* don't change MTU on "live" link (peer won't know) */
159 spin_lock_irqsave(&dev->lock, flags);
160 if (dev->port_usb)
161 status = -EBUSY;
162 else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
163 status = -ERANGE;
164 else
165 net->mtu = new_mtu;
166 spin_unlock_irqrestore(&dev->lock, flags);
167
168 return status;
169}
170
171static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
172{
173 struct eth_dev *dev = netdev_priv(net);
174
175 strlcpy(p->driver, "g_ether", sizeof p->driver);
176 strlcpy(p->version, DRIVER_VERSION, sizeof p->version);
177 strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version);
178 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info);
179}
180
181static u32 eth_get_link(struct net_device *net)
182{
183 struct eth_dev *dev = netdev_priv(net);
184 return dev->gadget->speed != USB_SPEED_UNKNOWN;
185}
186
187/* REVISIT can also support:
188 * - WOL (by tracking suspends and issuing remote wakeup)
189 * - msglevel (implies updated messaging)
190 * - ... probably more ethtool ops
191 */
192
193static struct ethtool_ops ops = {
194 .get_drvinfo = eth_get_drvinfo,
195 .get_link = eth_get_link
196};
197
198static void defer_kevent(struct eth_dev *dev, int flag)
199{
200 if (test_and_set_bit(flag, &dev->todo))
201 return;
202 if (!schedule_work(&dev->work))
203 ERROR(dev, "kevent %d may have been dropped\n", flag);
204 else
205 DBG(dev, "kevent %d scheduled\n", flag);
206}
207
208static void rx_complete(struct usb_ep *ep, struct usb_request *req);
209
210static int
211rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
212{
213 struct sk_buff *skb;
214 int retval = -ENOMEM;
215 size_t size = 0;
216 struct usb_ep *out;
217 unsigned long flags;
218
219 spin_lock_irqsave(&dev->lock, flags);
220 if (dev->port_usb)
221 out = dev->port_usb->out_ep;
222 else
223 out = NULL;
224 spin_unlock_irqrestore(&dev->lock, flags);
225
226 if (!out)
227 return -ENOTCONN;
228
229
230 /* Padding up to RX_EXTRA handles minor disagreements with host.
231 * Normally we use the USB "terminate on short read" convention;
232 * so allow up to (N*maxpacket), since that memory is normally
233 * already allocated. Some hardware doesn't deal well with short
234 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
235 * byte off the end (to force hardware errors on overflow).
236 *
237 * RNDIS uses internal framing, and explicitly allows senders to
238 * pad to end-of-packet. That's potentially nice for speed, but
239 * means receivers can't recover lost synch on their own (because
240 * new packets don't only start after a short RX).
241 */
242 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
243 size += dev->port_usb->header_len;
244 size += out->maxpacket - 1;
245 size -= size % out->maxpacket;
246
247 skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
248 if (skb == NULL) {
249 DBG(dev, "no rx skb\n");
250 goto enomem;
251 }
252
253 /* Some platforms perform better when IP packets are aligned,
254 * but on at least one, checksumming fails otherwise. Note:
255 * RNDIS headers involve variable numbers of LE32 values.
256 */
257 skb_reserve(skb, NET_IP_ALIGN);
258
259 req->buf = skb->data;
260 req->length = size;
261 req->complete = rx_complete;
262 req->context = skb;
263
264 retval = usb_ep_queue(out, req, gfp_flags);
265 if (retval == -ENOMEM)
266enomem:
267 defer_kevent(dev, WORK_RX_MEMORY);
268 if (retval) {
269 DBG(dev, "rx submit --> %d\n", retval);
270 if (skb)
271 dev_kfree_skb_any(skb);
272 spin_lock_irqsave(&dev->req_lock, flags);
273 list_add(&req->list, &dev->rx_reqs);
274 spin_unlock_irqrestore(&dev->req_lock, flags);
275 }
276 return retval;
277}
278
279static void rx_complete(struct usb_ep *ep, struct usb_request *req)
280{
281 struct sk_buff *skb = req->context;
282 struct eth_dev *dev = ep->driver_data;
283 int status = req->status;
284
285 switch (status) {
286
287 /* normal completion */
288 case 0:
289 skb_put(skb, req->actual);
290 if (dev->unwrap)
291 status = dev->unwrap(skb);
292 if (status < 0
293 || ETH_HLEN > skb->len
294 || skb->len > ETH_FRAME_LEN) {
295 dev->net->stats.rx_errors++;
296 dev->net->stats.rx_length_errors++;
297 DBG(dev, "rx length %d\n", skb->len);
298 break;
299 }
300
301 skb->protocol = eth_type_trans(skb, dev->net);
302 dev->net->stats.rx_packets++;
303 dev->net->stats.rx_bytes += skb->len;
304
305 /* no buffer copies needed, unless hardware can't
306 * use skb buffers.
307 */
308 status = netif_rx(skb);
309 skb = NULL;
310 break;
311
312 /* software-driven interface shutdown */
313 case -ECONNRESET: /* unlink */
314 case -ESHUTDOWN: /* disconnect etc */
315 VDBG(dev, "rx shutdown, code %d\n", status);
316 goto quiesce;
317
318 /* for hardware automagic (such as pxa) */
319 case -ECONNABORTED: /* endpoint reset */
320 DBG(dev, "rx %s reset\n", ep->name);
321 defer_kevent(dev, WORK_RX_MEMORY);
322quiesce:
323 dev_kfree_skb_any(skb);
324 goto clean;
325
326 /* data overrun */
327 case -EOVERFLOW:
328 dev->net->stats.rx_over_errors++;
329 /* FALLTHROUGH */
330
331 default:
332 dev->net->stats.rx_errors++;
333 DBG(dev, "rx status %d\n", status);
334 break;
335 }
336
337 if (skb)
338 dev_kfree_skb_any(skb);
339 if (!netif_running(dev->net)) {
340clean:
341 spin_lock(&dev->req_lock);
342 list_add(&req->list, &dev->rx_reqs);
343 spin_unlock(&dev->req_lock);
344 req = NULL;
345 }
346 if (req)
347 rx_submit(dev, req, GFP_ATOMIC);
348}
349
350static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
351{
352 unsigned i;
353 struct usb_request *req;
354
355 if (!n)
356 return -ENOMEM;
357
358 /* queue/recycle up to N requests */
359 i = n;
360 list_for_each_entry(req, list, list) {
361 if (i-- == 0)
362 goto extra;
363 }
364 while (i--) {
365 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
366 if (!req)
367 return list_empty(list) ? -ENOMEM : 0;
368 list_add(&req->list, list);
369 }
370 return 0;
371
372extra:
373 /* free extras */
374 for (;;) {
375 struct list_head *next;
376
377 next = req->list.next;
378 list_del(&req->list);
379 usb_ep_free_request(ep, req);
380
381 if (next == list)
382 break;
383
384 req = container_of(next, struct usb_request, list);
385 }
386 return 0;
387}
388
389static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
390{
391 int status;
392
393 spin_lock(&dev->req_lock);
394 status = prealloc(&dev->tx_reqs, link->in_ep, n);
395 if (status < 0)
396 goto fail;
397 status = prealloc(&dev->rx_reqs, link->out_ep, n);
398 if (status < 0)
399 goto fail;
400 goto done;
401fail:
402 DBG(dev, "can't alloc requests\n");
403done:
404 spin_unlock(&dev->req_lock);
405 return status;
406}
407
408static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
409{
410 struct usb_request *req;
411 unsigned long flags;
412
413 /* fill unused rxq slots with some skb */
414 spin_lock_irqsave(&dev->req_lock, flags);
415 while (!list_empty(&dev->rx_reqs)) {
416 req = container_of(dev->rx_reqs.next,
417 struct usb_request, list);
418 list_del_init(&req->list);
419 spin_unlock_irqrestore(&dev->req_lock, flags);
420
421 if (rx_submit(dev, req, gfp_flags) < 0) {
422 defer_kevent(dev, WORK_RX_MEMORY);
423 return;
424 }
425
426 spin_lock_irqsave(&dev->req_lock, flags);
427 }
428 spin_unlock_irqrestore(&dev->req_lock, flags);
429}
430
431static void eth_work(struct work_struct *work)
432{
433 struct eth_dev *dev = container_of(work, struct eth_dev, work);
434
435 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
436 if (netif_running(dev->net))
437 rx_fill(dev, GFP_KERNEL);
438 }
439
440 if (dev->todo)
441 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
442}
443
444static void tx_complete(struct usb_ep *ep, struct usb_request *req)
445{
446 struct sk_buff *skb = req->context;
447 struct eth_dev *dev = ep->driver_data;
448
449 switch (req->status) {
450 default:
451 dev->net->stats.tx_errors++;
452 VDBG(dev, "tx err %d\n", req->status);
453 /* FALLTHROUGH */
454 case -ECONNRESET: /* unlink */
455 case -ESHUTDOWN: /* disconnect etc */
456 break;
457 case 0:
458 dev->net->stats.tx_bytes += skb->len;
459 }
460 dev->net->stats.tx_packets++;
461
462 spin_lock(&dev->req_lock);
463 list_add(&req->list, &dev->tx_reqs);
464 spin_unlock(&dev->req_lock);
465 dev_kfree_skb_any(skb);
466
467 atomic_dec(&dev->tx_qlen);
468 if (netif_carrier_ok(dev->net))
469 netif_wake_queue(dev->net);
470}
471
472static inline int is_promisc(u16 cdc_filter)
473{
474 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
475}
476
477static int eth_start_xmit(struct sk_buff *skb, struct net_device *net)
478{
479 struct eth_dev *dev = netdev_priv(net);
480 int length = skb->len;
481 int retval;
482 struct usb_request *req = NULL;
483 unsigned long flags;
484 struct usb_ep *in;
485 u16 cdc_filter;
486
487 spin_lock_irqsave(&dev->lock, flags);
488 if (dev->port_usb) {
489 in = dev->port_usb->in_ep;
490 cdc_filter = dev->port_usb->cdc_filter;
491 } else {
492 in = NULL;
493 cdc_filter = 0;
494 }
495 spin_unlock_irqrestore(&dev->lock, flags);
496
497 if (!in) {
498 dev_kfree_skb_any(skb);
499 return 0;
500 }
501
502 /* apply outgoing CDC or RNDIS filters */
503 if (!is_promisc(cdc_filter)) {
504 u8 *dest = skb->data;
505
506 if (is_multicast_ether_addr(dest)) {
507 u16 type;
508
509 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
510 * SET_ETHERNET_MULTICAST_FILTERS requests
511 */
512 if (is_broadcast_ether_addr(dest))
513 type = USB_CDC_PACKET_TYPE_BROADCAST;
514 else
515 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
516 if (!(cdc_filter & type)) {
517 dev_kfree_skb_any(skb);
518 return 0;
519 }
520 }
521 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
522 }
523
524 spin_lock_irqsave(&dev->req_lock, flags);
525 /*
526 * this freelist can be empty if an interrupt triggered disconnect()
527 * and reconfigured the gadget (shutting down this queue) after the
528 * network stack decided to xmit but before we got the spinlock.
529 */
530 if (list_empty(&dev->tx_reqs)) {
531 spin_unlock_irqrestore(&dev->req_lock, flags);
532 return 1;
533 }
534
535 req = container_of(dev->tx_reqs.next, struct usb_request, list);
536 list_del(&req->list);
537
538 /* temporarily stop TX queue when the freelist empties */
539 if (list_empty(&dev->tx_reqs))
540 netif_stop_queue(net);
541 spin_unlock_irqrestore(&dev->req_lock, flags);
542
543 /* no buffer copies needed, unless the network stack did it
544 * or the hardware can't use skb buffers.
545 * or there's not enough space for extra headers we need
546 */
547 if (dev->wrap) {
548 struct sk_buff *skb_new;
549
550 skb_new = dev->wrap(skb);
551 if (!skb_new)
552 goto drop;
553
554 dev_kfree_skb_any(skb);
555 skb = skb_new;
556 length = skb->len;
557 }
558 req->buf = skb->data;
559 req->context = skb;
560 req->complete = tx_complete;
561
562 /* use zlp framing on tx for strict CDC-Ether conformance,
563 * though any robust network rx path ignores extra padding.
564 * and some hardware doesn't like to write zlps.
565 */
566 req->zero = 1;
567 if (!dev->zlp && (length % in->maxpacket) == 0)
568 length++;
569
570 req->length = length;
571
572 /* throttle highspeed IRQ rate back slightly */
573 if (gadget_is_dualspeed(dev->gadget))
574 req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH)
575 ? ((atomic_read(&dev->tx_qlen) % qmult) != 0)
576 : 0;
577
578 retval = usb_ep_queue(in, req, GFP_ATOMIC);
579 switch (retval) {
580 default:
581 DBG(dev, "tx queue err %d\n", retval);
582 break;
583 case 0:
584 net->trans_start = jiffies;
585 atomic_inc(&dev->tx_qlen);
586 }
587
588 if (retval) {
589drop:
590 dev->net->stats.tx_dropped++;
591 dev_kfree_skb_any(skb);
592 spin_lock_irqsave(&dev->req_lock, flags);
593 if (list_empty(&dev->tx_reqs))
594 netif_start_queue(net);
595 list_add(&req->list, &dev->tx_reqs);
596 spin_unlock_irqrestore(&dev->req_lock, flags);
597 }
598 return 0;
599}
600
601/*-------------------------------------------------------------------------*/
602
603static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
604{
605 DBG(dev, "%s\n", __func__);
606
607 /* fill the rx queue */
608 rx_fill(dev, gfp_flags);
609
610 /* and open the tx floodgates */
611 atomic_set(&dev->tx_qlen, 0);
612 netif_wake_queue(dev->net);
613}
614
615static int eth_open(struct net_device *net)
616{
617 struct eth_dev *dev = netdev_priv(net);
618 struct gether *link;
619
620 DBG(dev, "%s\n", __func__);
621 if (netif_carrier_ok(dev->net))
622 eth_start(dev, GFP_KERNEL);
623
624 spin_lock_irq(&dev->lock);
625 link = dev->port_usb;
626 if (link && link->open)
627 link->open(link);
628 spin_unlock_irq(&dev->lock);
629
630 return 0;
631}
632
633static int eth_stop(struct net_device *net)
634{
635 struct eth_dev *dev = netdev_priv(net);
636 unsigned long flags;
637
638 VDBG(dev, "%s\n", __func__);
639 netif_stop_queue(net);
640
641 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
642 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
643 dev->net->stats.rx_errors, dev->net->stats.tx_errors
644 );
645
646 /* ensure there are no more active requests */
647 spin_lock_irqsave(&dev->lock, flags);
648 if (dev->port_usb) {
649 struct gether *link = dev->port_usb;
650
651 if (link->close)
652 link->close(link);
653
654 /* NOTE: we have no abort-queue primitive we could use
655 * to cancel all pending I/O. Instead, we disable then
656 * reenable the endpoints ... this idiom may leave toggle
657 * wrong, but that's a self-correcting error.
658 *
659 * REVISIT: we *COULD* just let the transfers complete at
660 * their own pace; the network stack can handle old packets.
661 * For the moment we leave this here, since it works.
662 */
663 usb_ep_disable(link->in_ep);
664 usb_ep_disable(link->out_ep);
665 if (netif_carrier_ok(net)) {
666 DBG(dev, "host still using in/out endpoints\n");
667 usb_ep_enable(link->in_ep, link->in);
668 usb_ep_enable(link->out_ep, link->out);
669 }
670 }
671 spin_unlock_irqrestore(&dev->lock, flags);
672
673 return 0;
674}
675
676/*-------------------------------------------------------------------------*/
677
678/* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
679static char *dev_addr;
680module_param(dev_addr, charp, S_IRUGO);
681MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");
682
683/* this address is invisible to ifconfig */
684static char *host_addr;
685module_param(host_addr, charp, S_IRUGO);
686MODULE_PARM_DESC(host_addr, "Host Ethernet Address");
687
688
689static u8 __init nibble(unsigned char c)
690{
691 if (isdigit(c))
692 return c - '0';
693 c = toupper(c);
694 if (isxdigit(c))
695 return 10 + c - 'A';
696 return 0;
697}
698
699static int __init get_ether_addr(const char *str, u8 *dev_addr)
700{
701 if (str) {
702 unsigned i;
703
704 for (i = 0; i < 6; i++) {
705 unsigned char num;
706
707 if ((*str == '.') || (*str == ':'))
708 str++;
709 num = nibble(*str++) << 4;
710 num |= (nibble(*str++));
711 dev_addr [i] = num;
712 }
713 if (is_valid_ether_addr(dev_addr))
714 return 0;
715 }
716 random_ether_addr(dev_addr);
717 return 1;
718}
719
720static struct eth_dev *the_dev;
721
722
723/**
724 * gether_setup - initialize one ethernet-over-usb link
725 * @g: gadget to associated with these links
726 * @ethaddr: NULL, or a buffer in which the ethernet address of the
727 * host side of the link is recorded
728 * Context: may sleep
729 *
730 * This sets up the single network link that may be exported by a
731 * gadget driver using this framework. The link layer addresses are
732 * set up using module parameters.
733 *
734 * Returns negative errno, or zero on success
735 */
736int __init gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN])
737{
738 struct eth_dev *dev;
739 struct net_device *net;
740 int status;
741
742 if (the_dev)
743 return -EBUSY;
744
745 net = alloc_etherdev(sizeof *dev);
746 if (!net)
747 return -ENOMEM;
748
749 dev = netdev_priv(net);
750 spin_lock_init(&dev->lock);
751 spin_lock_init(&dev->req_lock);
752 INIT_WORK(&dev->work, eth_work);
753 INIT_LIST_HEAD(&dev->tx_reqs);
754 INIT_LIST_HEAD(&dev->rx_reqs);
755
756 /* network device setup */
757 dev->net = net;
758 strcpy(net->name, "usb%d");
759
760 if (get_ether_addr(dev_addr, net->dev_addr))
761 dev_warn(&g->dev,
762 "using random %s ethernet address\n", "self");
763 if (get_ether_addr(host_addr, dev->host_mac))
764 dev_warn(&g->dev,
765 "using random %s ethernet address\n", "host");
766
767 if (ethaddr)
768 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
769
770 net->change_mtu = eth_change_mtu;
771 net->hard_start_xmit = eth_start_xmit;
772 net->open = eth_open;
773 net->stop = eth_stop;
774 /* watchdog_timeo, tx_timeout ... */
775 /* set_multicast_list */
776 SET_ETHTOOL_OPS(net, &ops);
777
778 /* two kinds of host-initiated state changes:
779 * - iff DATA transfer is active, carrier is "on"
780 * - tx queueing enabled if open *and* carrier is "on"
781 */
782 netif_stop_queue(net);
783 netif_carrier_off(net);
784
785 dev->gadget = g;
786 SET_NETDEV_DEV(net, &g->dev);
787
788 status = register_netdev(net);
789 if (status < 0) {
790 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
791 free_netdev(net);
792 } else {
793 DECLARE_MAC_BUF(tmp);
794
795 INFO(dev, "MAC %s\n", print_mac(tmp, net->dev_addr));
796 INFO(dev, "HOST MAC %s\n", print_mac(tmp, dev->host_mac));
797
798 the_dev = dev;
799 }
800
801 return status;
802}
803
804/**
805 * gether_cleanup - remove Ethernet-over-USB device
806 * Context: may sleep
807 *
808 * This is called to free all resources allocated by @gether_setup().
809 */
810void gether_cleanup(void)
811{
812 if (!the_dev)
813 return;
814
815 unregister_netdev(the_dev->net);
816 free_netdev(the_dev->net);
817
818 /* assuming we used keventd, it must quiesce too */
819 flush_scheduled_work();
820
821 the_dev = NULL;
822}
823
824
825/**
826 * gether_connect - notify network layer that USB link is active
827 * @link: the USB link, set up with endpoints, descriptors matching
828 * current device speed, and any framing wrapper(s) set up.
829 * Context: irqs blocked
830 *
831 * This is called to activate endpoints and let the network layer know
832 * the connection is active ("carrier detect"). It may cause the I/O
833 * queues to open and start letting network packets flow, but will in
834 * any case activate the endpoints so that they respond properly to the
835 * USB host.
836 *
837 * Verify net_device pointer returned using IS_ERR(). If it doesn't
838 * indicate some error code (negative errno), ep->driver_data values
839 * have been overwritten.
840 */
841struct net_device *gether_connect(struct gether *link)
842{
843 struct eth_dev *dev = the_dev;
844 int result = 0;
845
846 if (!dev)
847 return ERR_PTR(-EINVAL);
848
849 link->in_ep->driver_data = dev;
850 result = usb_ep_enable(link->in_ep, link->in);
851 if (result != 0) {
852 DBG(dev, "enable %s --> %d\n",
853 link->in_ep->name, result);
854 goto fail0;
855 }
856
857 link->out_ep->driver_data = dev;
858 result = usb_ep_enable(link->out_ep, link->out);
859 if (result != 0) {
860 DBG(dev, "enable %s --> %d\n",
861 link->out_ep->name, result);
862 goto fail1;
863 }
864
865 if (result == 0)
866 result = alloc_requests(dev, link, qlen(dev->gadget));
867
868 if (result == 0) {
869 dev->zlp = link->is_zlp_ok;
870 DBG(dev, "qlen %d\n", qlen(dev->gadget));
871
872 dev->header_len = link->header_len;
873 dev->unwrap = link->unwrap;
874 dev->wrap = link->wrap;
875
876 spin_lock(&dev->lock);
877 dev->port_usb = link;
878 link->ioport = dev;
879 spin_unlock(&dev->lock);
880
881 netif_carrier_on(dev->net);
882 if (netif_running(dev->net))
883 eth_start(dev, GFP_ATOMIC);
884
885 /* on error, disable any endpoints */
886 } else {
887 (void) usb_ep_disable(link->out_ep);
888fail1:
889 (void) usb_ep_disable(link->in_ep);
890 }
891fail0:
892 /* caller is responsible for cleanup on error */
893 if (result < 0)
894 return ERR_PTR(result);
895 return dev->net;
896}
897
898/**
899 * gether_disconnect - notify network layer that USB link is inactive
900 * @link: the USB link, on which gether_connect() was called
901 * Context: irqs blocked
902 *
903 * This is called to deactivate endpoints and let the network layer know
904 * the connection went inactive ("no carrier").
905 *
906 * On return, the state is as if gether_connect() had never been called.
907 * The endpoints are inactive, and accordingly without active USB I/O.
908 * Pointers to endpoint descriptors and endpoint private data are nulled.
909 */
910void gether_disconnect(struct gether *link)
911{
912 struct eth_dev *dev = link->ioport;
913 struct usb_request *req;
914
915 WARN_ON(!dev);
916 if (!dev)
917 return;
918
919 DBG(dev, "%s\n", __func__);
920
921 netif_stop_queue(dev->net);
922 netif_carrier_off(dev->net);
923
924 /* disable endpoints, forcing (synchronous) completion
925 * of all pending i/o. then free the request objects
926 * and forget about the endpoints.
927 */
928 usb_ep_disable(link->in_ep);
929 spin_lock(&dev->req_lock);
930 while (!list_empty(&dev->tx_reqs)) {
931 req = container_of(dev->tx_reqs.next,
932 struct usb_request, list);
933 list_del(&req->list);
934
935 spin_unlock(&dev->req_lock);
936 usb_ep_free_request(link->in_ep, req);
937 spin_lock(&dev->req_lock);
938 }
939 spin_unlock(&dev->req_lock);
940 link->in_ep->driver_data = NULL;
941 link->in = NULL;
942
943 usb_ep_disable(link->out_ep);
944 spin_lock(&dev->req_lock);
945 while (!list_empty(&dev->rx_reqs)) {
946 req = container_of(dev->rx_reqs.next,
947 struct usb_request, list);
948 list_del(&req->list);
949
950 spin_unlock(&dev->req_lock);
951 usb_ep_free_request(link->out_ep, req);
952 spin_lock(&dev->req_lock);
953 }
954 spin_unlock(&dev->req_lock);
955 link->out_ep->driver_data = NULL;
956 link->out = NULL;
957
958 /* finish forgetting about this USB link episode */
959 dev->header_len = 0;
960 dev->unwrap = NULL;
961 dev->wrap = NULL;
962
963 spin_lock(&dev->lock);
964 dev->port_usb = NULL;
965 link->ioport = NULL;
966 spin_unlock(&dev->lock);
967}
diff --git a/drivers/usb/gadget/u_ether.h b/drivers/usb/gadget/u_ether.h
new file mode 100644
index 000000000000..ca8ce467d880
--- /dev/null
+++ b/drivers/usb/gadget/u_ether.h
@@ -0,0 +1,83 @@
1/*
2 * u_ether.h -- interface to USB gadget "ethernet link" utilities
3 *
4 * Copyright (C) 2003-2005,2008 David Brownell
5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
6 * Copyright (C) 2008 Nokia Corporation
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23#ifndef __U_ETHER_H
24#define __U_ETHER_H
25
26#include <linux/err.h>
27#include <linux/if_ether.h>
28#include <linux/usb/composite.h>
29#include <linux/usb/cdc.h>
30
31/*
32 * This represents the USB side of an "ethernet" link, managed by a USB
33 * function which provides control and (maybe) framing. Two functions
34 * in different configurations could share the same ethernet link/netdev.
35 *
36 * There is currently a limitation that one instance of this function
37 * may be present in any given configuration.
38 */
39struct gether {
40 struct usb_function func;
41
42 /* updated by gether_{connect,disconnect} */
43 struct eth_dev *ioport;
44
45 /* endpoints handle full and/or high speeds */
46 struct usb_ep *in_ep;
47 struct usb_ep *out_ep;
48
49 /* descriptors match device speed at gether_connect() time */
50 struct usb_endpoint_descriptor *in;
51 struct usb_endpoint_descriptor *out;
52
53 bool is_zlp_ok;
54
55 u16 cdc_filter;
56
57 /* hooks for added framing, as needed for RNDIS and EEM.
58 * we currently don't support multiple frames per SKB.
59 */
60 u32 header_len;
61 struct sk_buff *(*wrap)(struct sk_buff *skb);
62 int (*unwrap)(struct sk_buff *skb);
63
64 /* called on network open/close */
65 void (*open)(struct gether *);
66 void (*close)(struct gether *);
67};
68
69#define DEFAULT_FILTER (USB_CDC_PACKET_TYPE_BROADCAST \
70 |USB_CDC_PACKET_TYPE_ALL_MULTICAST \
71 |USB_CDC_PACKET_TYPE_PROMISCUOUS \
72 |USB_CDC_PACKET_TYPE_DIRECTED)
73
74
75/* netdev setup/teardown as directed by the gadget driver */
76int gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]);
77void gether_cleanup(void);
78
79/* connect/disconnect is handled by individual functions */
80struct net_device *gether_connect(struct gether *);
81void gether_disconnect(struct gether *);
82
83#endif /* __U_ETHER_H */